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E. B. MERRIAM.

ELECTRIC SWITCH.

APPLICATION H LED JUNE 1. 1916.

1,306,551. PatentedJune 10, 1919.

xv y l A l Inventor: 1551-61 B. erram,

His nttomeg,

surface of oil or other insulat' The object of my invention is to provide UNITED, sTATEs vvPn'rnm OFFICE. .y

nzaa n. MEimImQor sCHmmcTADY, NEW Yonx, AssIeNon. To GENERAL ELECTRIC COMPANY, A'CORPOBA'IION 0F NEW, YORK.

' ELECTRIC SWITCH.

specificati@ of Letters patent.- Patented June 1(),19119 ."Applioation led June 7, 1916. Serial No. 102,211.

l To all 'whom it may concern.' Y'

lBeit known that I, EzRA B. MERRIAM, a

citizen -of the United States, residing atv Schenectady, in the county of Schenectady,

5 State of New York, have invented certain and in particular to electric switches in which the contacts are opened beneath the fluid.

a novel and improved electric switch of the oil break type. and more specifically to pro- ;vide an oil break switch having novel -and improved means for preventing the ejection of oil from vsuch switches under the pressures existingin the switches when the 'contacts separate and for absorbing'the energy of the oil within the switch.

In switches in which the contacts separate under oil, various' means have been suggested and have been used for baliiing the oil within the switch consisting of plates having staggered 'openings and other arrangements for decreasing the velocity of `the oil. .I provide howeverl a dilferent type of means than heretofore known which operates as an energy absorbing device to catch the oil and obsorb its energy within the switch. v

My invention will best be understood in connection with the accompanying drawings in which, merely for purposes of illustration,

I have shown some of the .various forms in lwhich my invention vmay be embodied and in which. Figure 1 is a vertical section of one form of switch' constructed in accord- 40 ance with my invention; Figs. 2, 3,v 4 and 5 are plan views of portions of my switch shown in Fig. I; Fig.-6 is a sectional view 'of iagportion of a, ysimilar for-m of switch, eml.

swltch shown in Fig. 6; Fig. 8 is a sectional view ofa portion of a switch showing an- 10, and 11 are plan views of sectional view of a. portion of asimilar form ymgfmy invention in a modiiied form;y Fig. 7 is a detail view ofaportio'n of the means of two relatively movable coperating contacts, such as a stationary or fixed contact or contact member 2 mounted at the bottom of the oilv pot V1' and a movable contact or'contact member 3 .in the form of a rod movable longitudinally of the' oil pot 1 by any suitable mechamsm and slidably mounted in 'a hollow insulator 4 carried by V-the Itop of the oil pot. The separation of the contacts draws an arc in the insulating uid, and the pressure produced by the arc is relieved by means of suitable vente 5 in the top ofthe oil pot. The insulating iluid is retained inthe neighborhood of the arc and is directedl against the arc to extinguish it, by means of a member or partition 6 provided with an opening or vent 7 and mounted above the Xed Contact 2 with its edges in engagement with the lining of .the -oil pot-1, so that the fixed contact 2 is inclosed 1n a pressure retaining chamber or vessel of which the partition 6 forms one wall and in' which' the oil is put under pressure .by the action of the arc formedbetween the contacts as the circuit is being opened. Thepartition is held in place against pressure generated by the arc in the pressure retaining chamber by suitable lsupporting members 8.

- When a switch constructed as above described isopened, the movable contact 3 separates from the i/xed contact? and moves' upward through thev opening 7 v1n the plate or member 6, thereby drawing an arc through the opening. The member 6 confines the 011 put under lpressure by the arc, 1u the pressure retaining chamber and directs 1t -through the vent 7 against the arc tovextinguish it, with the result'that the -oil and' gases are projected through the vent 7 in a,

)et or stream which tends to spread out like a fountain. j

In accordancewith my invention, I provide means within the oil vessel whereby the oil and gases ejected from the pressure retaining chamber are separated and the gases allowed to escape from the oilpot while the oil is intercepted and directed to the sidesof the vessel' where its energy is absorbed in pocket or intercepting members.

This energy absorbing means consists of intercept-ing members or plates 9 and 10 and a baille plate 11 which are suitably seof 4any entrapped gases.

gases are ejected from the pressure retaining' cured to supporting members 8 within the oil pot and which are provided with central' openings 12, 13 and 14, respectively, as best shown in Figs. 2, 3 and 4, respectively. The

in tercepting members 9 and 10 are mountedsubstantially in engagement with the sides of the oil pot and are of a conliguration forming an annular pocket or recess between the sides of the oil pot and the openings 12 and 13, concentric with the movable contact 3 and with the openings. Thesebell shaped intercepters are made of metal and at the topfof each pocket ormrecess ofthe intercepters are preforations 15 to allow the escape As the oil and ing with only slightclearance. Owing to the smaller opening 13 in the member 10, the

pocket or recess of member v10 is somewhat larger, the inner sides of the pocket extending farther toward the center of the oil pot and into the oil stream. The oil, therefore,

.- that 4rises through the opening 12 in intercepter 9 is thereby deected into the pocket 1 of member 10 and the gases, if they have not already spent their velocity, follow the movable contact through opening 13 of inter- Icepter 10 and around baile 11 and finally through vents 5 out of the oil pot. If, under.

unusual circumstances, there is some oil ejected through the opening 13 of intercepv ter 10, thls oil strikes the baille 11 and is deflected and prevented from l escaping through the vents 5.. o* f By my novel energy absorbing means described, the oil is not caused to follow a tortuous path or isit splashed about by strikingiat baile plates but'the oil is directed into the pockets of the bell shaped intercepters .9 and 10, which act to catchc the oil yand absorbits energy in the same manner "'==as the pocket formed in a baseball glove catches a baseball. The oil is caught by .these pockets or recesses, its energy absorbed and then the -oilallowed to drop back into cape through the perforations 15. The intercepters 9 and 10, being of metal, act to coolthe heated oil and arc gases and prevent thereby the liability of explosions in the switch. The difference in principle and in` operation between 'the interception of the upwardly ejected oil by the bell shaped intercepters 9 and 10, and the absorption of its energy and the baffling action of substantially lflat bales of ordinary construction may be compared in principle to the pouring of a liquid upon a flat plateor into abasin. With a ila-t plate, the liquid is delected vin all directions, whereas in a basin the fluid is not deflected but is caught and rstained therein. In a switch having the ordinary baille construction, the oil is ejected upward against a substantially fiat surface and is deected' in all directions wherein with the bell shaped i'ntercepters, the oil is not deflected but is caught and its energy expended vand then the oil isJ allowed to freelyvfalll into the oil reservoir at the bottom .of the oil pot. meansl and the members 6 and 11 with their supportingV members 8 are arranged in unit construction, which unit is removably posi-, tioned in the'oil pot.

In Fig. 6, I have shown a slightly diierent form of my energy absorbing device embodied in a switch of the same type as that shown in Fig. 1. In this device, the intercepter 9 is smaller than the corresponding intercepter shown in Fig. 1 havinga smaller central opening 12 and is spaced away from the walls of the oil pot 1 whereby a greater -portion of the oil ejected from opening 7 'is caught in the pocket ofthe intercepter. v

This intercepter ismore clearlyshown in Fig. 7. The metallic bell shaped intercepting members may be made, in general, 1n l two forms differing only slightly from each other in coniiguration. The members 9 and 10 shown in Figs. 1 and i are spun into the desired shape whereas the iiitercepters ,16 and 17 shown in Fig. 8,-ffor switches oper- .v

ating in higher potential circuits, are cast in the desired shape with perforations 15, 'the cast members being of a little more ruggedv construction. The intercepters 16 and 17 are shown more in detail in Figs. 10 "and 11 respectively and are provided with My venergy absorbingA central openings, into which openings insulating members or sleeves `18 and 19 are respectively inserted, which sleeves are preferably substantially tubular in form to produce cylindrical 5r tubular openings or passages 20 and 21 respectively'throu'gh which the movable `contact member 3 passes, the insulating members 18 and 19 serving to insulate the movable contact from the metal intercepters. In this construction an lextra baie plate 22 is provided at the top of the oil pot adjacent the vents y and having' a central opening 23' as best shown in Fig. 9.

In Fig. 12, I have shown my energy a'b- 5 sorbing means as comp-rising an intercepting member of slightly different conguraftion. In this construction mounted on the' partition or member 6 insulated therefrom is a deiiecting member 24, preferably l0 -of substantially inverted conical shape, having an opening adjacent and in alinement with the. opening 7 in member 6. The openl ing in the ,defiector 24 is much smaller than Athe opening-7 sothat the Vflaring sides of the deflector extend i'nto the path of the u-pward streani. of oil and act to deflect the oi'l to thesides of the oil pot 1. Mounted near the top of the oil p'ot 1 is an intercepting member 25, the innersides of which extend down the center of the oil pot to form between the sides a central elongated or tubular chamber. The intercepter 25 has an openin 26 which is adjacent and just above the de ector 24, the edges offthe opening being turned in somewhat'to deflect the oil. Between the inner sides of the intercepter 25 and the walls of -the oil pot 1 is formed an annular passage closed at its upper end and forming |a very deep pocket into which the 30 oil is directed by the deiector 24, and its energy absorbed in the same manner as already described. By this construction, the oil is deflected into one interce ter having a deep recess or pocketwhile the arc gases are separated from |the oil and rise through the center of the oil pot following the moving contact. into lthe elongated chamber formed by the sides of the deflector 25.

' My invention may be embodied in other 40 forms than those shown and described andv I, therefore, do not wish to berestricted to the precise construction disclosed but in-- tend to cover. bythe appended claims changes and modifications which are within the scope of lmy invention and will .be apparent to those skilled in the art. Wha-t I claim as Ynew anddesireto secure Aby Letters Paten-t of the United States, is: U 1. A circuit interrupting device comprising 'a-pressure retaining chamber for containing o'1l and having a vent in one wall thereof, relatively movable coperating' contacts separable in said chamber, meansvv for absorbing the energy of the oil ejected from A Vsaid vent as'saidcontacts separate comprising intercepting membersshaped to provide annular pockets into Which-the oil is defiected-and itsenergyy absorbed.

2. A circuit interrupting device comprising a pressure'retaining chamber vfor con-f talmng oil andvhaving` a vent in vone wal. thereof, 'relatively' movable coperating .con tacts separable` in said chamber, interceptlng means above said ven-t comprising bell vshaped members for catching the oil ejectedA 1,306,551. i y, m 3

from said vent as said contacts separate and absorbing its' energy within the interrupting device. A l

3. A circuit interrupting device comprising a pressure retainlng chamber for con- 7o ta1ning oil land, having a vent in one Wall thereof, relatively movable coperating contacts separable in said chamber,- metallic bell shaped members mounted in the space above said ventand provided with substantially closed annular pockets into which the ,oil is directed as it is ejected from said vent and its energy absorbed. l 4. A circuit'in-terrupting device comprising a vessel containing oil, a pressure. re-

taining` chamber within said vessel having a vent in one wall thereof, relatively movable coperating contacts separable in said chamber, an energy absorbing means for the oil ejected through said vent as said contacts separate comprising a unitary structure rej movably positioned within said oil vessel and consisting of bell shaped intercepting members ha central -openings through whichvthe movable contact passes, said inl rtercepting members being provided with annulla-r recees intowhich the oil is deflected and its energy absorbed.

5.. An oil switch comprising a vessel' for containing oil, a pressure retaining chamber .within said vessel having a vent in one Wall thereof, relatively movable coperating contacts separable in said chamber, means for absorbing the energy of the oil as it is ejected through said vent comprising metallic bell shaped intercepters mounted substantially in engagement with the sides of said oil vessel and having central openings, said intercepters forming pockets concentric with said openings having perforations at the tops thereof, insulating members mounted in said openings 'and providing cylindrical passages through which said Vmovable contact passes'. f X

6. An oil switch comprising a vessel for 'containing oil, a pressure retaining chamber within said vessel having a vent in one wall thereof, relati-vely movable coperating con` tacts separable in said chamber, a bell lshaped member mounted between said vent 115 and the top of the oil vessel substantially "closing said vessel except for a central opening in said member, said member being shaped to provide an annular pocket` for catching and interoepting the oil as it is ejected upward whereby the .energy o f the oil is absorbed within the switch.

7. An oil switch comprising apressure retaining chamber containing oil and having a vent' in one wall thereof,.fixed and 125 movable'perating contacts separable in v said chamber, a bell shaped intercepting memberl mounted above said pressure retaining chamber provided with a central open- Y lng and forminga pocket concentric thereso f I through which said movable Contact passes with slight clearence end forming a, pocket concentric therewith, the sldes of said pocket 'adjacent said opening extending into the Tpzlith Iof i'id ejected through the opening of s a'id first mentioned interceptingtmember, said pockets constituting saidgbell shaped 10 `members actingto catch the oil and absorb its energy.

In Vwitness whereof, I have hereunto set my hand this 5th day of June, 1916.

` EZRA B. MERRIAM. 

